.nav_body{
  height: 45px;
}
.nav_body .nav{
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  height: 45px;
  justify-content: space-between;
  align-items: center;
  background-color: pink;
  color: #fff;
  font-size: 20px;
  box-sizing: border-box;
  padding: 0 10px;
}
.nav .iconfont{
  font-size: 25px;
}